Myth, or mandate: Are you required to memorize your driver’s license number?

When I was 16 I lived in fear of forgetting those almighty nine digits. If you flubbed them up while reciting them to a police officer, he might . . . well, I wasn’t sure what he might do. Give you a ticket? Haul you in? Bottom line: I never wanted to find out.

I’ve now driven for 25 years, and have written tens of thousands of words about the rules of the road. Yet, I’m still clueless as to whether the whole thing about memorizing your license number is legend or law. It’s about time we found out.

Today we search for the truth in some popular driving myths. These can’t be real ... or can they?

4 . . . 3 . . . um . . . 5?

As things stand, I don’t know my license number, at all. And you probably know why: To protect against identity theft, the state has done away with using Social Security numbers as license numbers. My new number starts with an S, and from there, I couldn’t tell you.

But what if I get pulled over for speeding and am asked my license number? Is the excuse that it has changed good enough?

“You do not need to memorize your driver’s license number,” said David Procopio, spokesman for the State Police.

“Obviously, it was easier for a driver to remember when the license number was the same as his or her Social Security number. Since the advent of S numbers, it is obviously harder to memorize, and you do not have to.”

Phew.

No place like home

Most accidents happen close to home — you’ve heard this one, right? It belies the idea that the more familiar the road, the more easily distracted we tend to be.

But what’s the definition of “close?” And do the numbers back it up?

The saying, insurance industry experts say, can be traced to Progressive Insurance, one of the country’s biggest auto insurance providers. As part of a “claims satisfaction survey” conducted in 2001, the company asked more than 11,000 people who reported a crash how far from their homes the accident occurred.

‘You can’t make out the number at all’ on a faded license plate.

“The survey found that 52 percent of reported crashes occurred 5 miles or less from home, and a whopping 77 percent occurred 15 miles or less from home,” reads Progressive’s website.

The study also showed that 23 percent of accidents happened within a mile of home — that’s pretty close — while only 1 percent occurred beyond a 50-mile radius.

So the saying is true, or is it?

To be clear, I think Progressive did a fine job with its study. But I find it very odd that no one else has corroborated the findings.

The National Highway Traffic Safety Administration told me it has never studied how often accidents happen close to home. The Insurance Institute for Highway Safety, which publishes studies on myriad topics related to accidents, has no data to back up Progressive’s report. Another respected information warehouse, The New York-based Insurance Information Institute, said the same.

From what I gather, no other major insurance company has replicated Progressive’s study. Though 11 years have passed, Progressive officials told me they’ve yet to do a follow-up. So that’s the proof: one study of just 11,000 drivers.

Progressive’s study, meanwhile, fails to tell us what we really want to know: On average, are you more likely to get into an accident when running to the post office versus driving somewhere you’ve never been?

That is to say, are the odds of getting into an accident greater, or less, when driving on familiar roads?

“Obviously, we tend to drive close to home, so more accidents” should occur then, said Dick Luedke, a spokesman for State Farm Insurance.

“To truly answer [your] question, you would need to find data on where accidents occur relative to where those who have the accidents live, and where we drive all of our miles relative to where we live.”

That information, alas, doesn’t exist. The best I could find was the National Household Travel Study, a federal report that says the average person drives 12 miles a day to work and about 35 miles a day in all.

Those numbers make it appear that almost all driving is local, yet Progressive’s study showed that nearly a quarter of all accidents happen more than 15 miles from home. One might interpret that to mean that unfamiliar roads are, in fact, more dangerous.

“The problem with these types of studies is that they can be skewed in so many different ways,” said Loretta Worters of the Insurance Information Institute. “It’s not a clear thing.”

I wholeheartedly agree.

Ghost plates

Our last urban myth made me chuckle. When the reflective coating wears off your license plate, it supposedly can’t be read by toll-booth cameras. That means you could evade a toll, and they’d never know!

For the truth, I called Mark LaFrance, project manager for vehicle safety and compliance services for the Registry of Motor Vehicles. Oh, did he surprise me.

“If all the reflective [component] is gone from the license plate, it just looks like gray metal to the camera,” he said. “You can’t make out the number at all. It’s pretty amazing.”

But ghost plates aren’t a huge issue, he stressed. When a plate has lost its luster, it will fail inspection — by law a plate must be legible at a distance of at least 60 feet at night — and you’ll be forced to get new plates. “By and large, 99 percent of the plates out there will reflect just fine,” LaFrance said.

You’d imagine that older, green-and-white plates would account for the remaining 1 percent. But not necessarily, LaFrance said.

“It kind of depends how much salt and how much sun and how old the plate is,’’ he said. “Some older folks put the car with a green plate in a garage and it never comes out, so it still reflects.”

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